55042421 has 16 divisors (see below), whose sum is σ = 64963584. Its totient is φ = 45650304.

The previous prime is 55042399. The next prime is 55042423. The reversal of 55042421 is 12424055.

It is a happy number.

It is not a de Polignac number, because 55042421 - 2²² = 50848117 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55042423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57281 + ... + 58233.

It is an arithmetic number, because the mean of its divisors is an integer number (4060224).

Almost surely, 2^55042421 is an apocalyptic number.

It is an amenable number.

55042421 is a deficient number, since it is larger than the sum of its proper divisors (9921163).

55042421 is a wasteful number, since it uses less digits than its factorization.

55042421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1220.

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 55042421 is about 7419.0579590673. The cubic root of 55042421 is about 380.3929937052.

Adding to 55042421 its reverse (12424055), we get a palindrome (67466476).

The spelling of 55042421 in words is "fifty-five million, forty-two thousand, four hundred twenty-one".